Understanding the Korean dialysis cohort for mineral, vascular calcification, and fracture (ORCHESTRA) Study: Design, method, and baseline characteristics.

INTRODUCTION: End-stage renal disease (ESRD) is a growing disease in Korea and worldwide and is an important condition that affects patient outcomes. In order to provide optimal management for mineral disturbance, vascular calcification, and bone disease of ESRD patients, the ORCHESTRA study (Korean dialysis cohort for mineral, vascular calcification, and fracture) was conducted and enrolled Korean dialysis patients.

METHODS: Sixteen university-affiliated hospitals and one Veterans Health Service Medical Center participated in this study. This prospective cohort study enrolled approximately 900 consecutive dialysis patients between May 2019 and January 2021. Enrolled subjects were evaluated at baseline for demographic information, laboratory tests, radiologic imaging, and bone mineral densitometry (BMD) scans. After enrollment, regular assessments of patients were performed and their biospecimens were collected according to the study protocol. Primary outcomes were occurrence of major adverse cardiovascular events (MACE), invasive treatment for peripheral artery disease (PAD), and osteoporotic fractures. Secondary outcomes were hospitalization for cerebro-cardiovascular disease or progression of abdominal aortic calcification (AAC). Participants will be assessed for up to three years to determine whether primary or secondary outcomes occur.

RESULTS: From May 2019 to January 2021, all participating centers recruited 900 consecutive dialysis patients, including 786 undergoing hemodialysis (HD) and 114 undergoing peritoneal dialysis (PD). The mean age of subjects was 60.4 ± 12.3 years. Males accounted for 57.7%. The mean dialysis vintage was 6.1 ± 6.0 years. The HD group was significantly older, had a longer dialysis vintage, and more comorbidities. Overall, the severity of vascular calcification was higher and the level of BMD was lower in the HD group than in the PD group.

CONCLUSION: This is a nationwide, multicenter, prospective cohort study that focuses on CKD-mineral and bone disorder (CKD-MBD) and aims to provide clinical evidence to establish optimal treatment guidelines for Asian dialysis patients.